1. Field
The present application relates to a flare determination apparatus, an image processing apparatus, and a storage medium storing a flare determination program.
2. Description of the Related Art
Conventionally, an imaging element in which a plurality of pixels for focus detection are arranged on a part of a light-receiving surface on which a plurality of imaging pixels are two-dimensionally arranged, has been known (refer to Japanese Unexamined Patent Application Publication No. 2009-303194). The plurality of imaging pixels have spectral characteristics corresponding to respective plural color components, and further, the pixels for focus detection (focus detecting pixels) have spectral characteristics which are different from the spectral characteristics of the plurality of imaging pixels. From the plurality of imaging pixels, signals for generating an image are read to determine pixel values of the imaging pixels, and further, from the focus detecting pixels, signals for focus detection are read to determine pixel values of the focus detecting pixels. When performing pixel interpolation, a pixel value of a missing color component out of pixel values of the imaging pixels is interpolated, and an imaging pixel value corresponding to a position of the focus detecting pixel is interpolated.
In the invention described in Japanese Unexamined Patent Application Publication No. 2009-303194, in order to perform interpolation processing with respect to a focus detecting pixel, an interpolation pixel value of the focus detecting pixel is generated by using pixel values of imaging pixels positioned in a neighborhood of the focus detecting pixel, an evaluation pixel value being a pixel value when the neighboring imaging pixel has the same spectral characteristics as those of the focus detecting pixel is calculated, a high frequency component of image is calculated by using a pixel value of the focus detecting pixel and the evaluation pixel value, and the high frequency component is added to the interpolation pixel value to calculate a pixel value of imaging pixel corresponding to a position of the focus detecting pixel.
Generally, in an image processing apparatus, when flare is generated between pixels in the periphery of a light receiving part in an imaging element by reflected light from a wiring region, color mixing is caused by crosstalk in which incident light between micro-lenses leaks into neighboring pixels in the periphery of the light receiving part. When such a phenomenon occurs, not only the focus detecting pixel but also pixels therearound is affected and the focus detecting pixel having received the color mixing by the above-described pixel interpolation and pixels therearound appear as an interpolation residual which provides uncomfortable feeling to a human eye. When the occurrence of this flare can be preliminarily detected, it becomes possible to perform the above-described processing related to the pixel interpolation appropriately, but there is a problem in which a color component range of the color mixing caused by the flare is different depending on a light source type and it is difficult to detect the flare appropriately.